Hydraulic power transmission uses a liquid medium to transmit energy to control force and movement in innumerable industrial and mobile systems. Hydraulic fluid refers to liquids used for this purpose.
Hydraulic fluids may be water-based and non-water based. Water-based hydraulic fluids include water/glycol hydraulic fluids used for high pressure applications (below about 3,000 psig), water-in-oil emulsion hydraulic fluids used for medium-pressure applications (below about 800 psig) and oil-in-water emulsion hydraulic fluids typically used for low pressure applications (below about 300 psig). Non water-based hydraulic fluids generally include phosphate ester based hydraulic fluids, polyol ester hydraulic fluids, mineral oils, or synthetic oil blends.
Fire-resistant fluids commonly include oil-in-water emulsions classified as ISO-type HFAE, water-in-oil emulsions, ISO-type HFB, water-glycol solutions, ISO-type HFC, phosphate esters, ISO-type HFDR and organic esters, ISO-type HFDU. Water glycol fluids have proven to be excellent fire-resistant fluid options. It is desirable to provide and utilize cost-effective hydraulic fluids and fire-resistant fluids that are green and derived from renewable sources.